The first death metal CD i got was Scar Symmetry's Pitch Black Progress, that was a good gateway into the genre and for black metal I listened to Satyricon's latest one then got steadily heavier. Might work for you. And add Public Enemy and El-P onto Fort23's list. Electronica = Daft Punk. Good luck with all that.

Thom Yorke's solo album is pretty good Electronica, especially if you like Radiohead (and you do). I'd have to recommend Air above all, though, they're pretty tight. "Moon Safari" and "Talkie Walkie" are both great albums.

Now, for Death Metal, do you have any of Death's albums, perchance? "The Sound of Perseverance" is supposed to be quite excellent.